Weed of the Week:  Horsetail Equisetum arvense

Laurence Gale MScin Consultancy

Weed of the Week: Horsetail Equisetum arvense

By Laurence Gale MSc


Weeds are very good competitors and take advantage of any opportunities to colonise turf situations, particularly when the sward is under stress and weak, leaving bare soil areas for weeds to populate. Weeds have many mechanisms and characteristics that enable them to do this, having thick waxy cuticle leaves that can be resistant to some chemicals, fast reproduction methods, the ability to reseed in 6 week cycles and deep tap roots enabling the weed to survive in compacted dry ground conditions.

Weeds have one of three life cycles: annual; biennial or perennial.

  • Annual weeds: Live for a single season. These weeds germinate from seed in the spring or summer, flower and then die.
  • Biennial weeds: Live for two seasons. During the first growing season, these weeds remain in a vegetative stage and, in the following year, produce flowers, set seed and die.
  • Perennial weeds: Live for multiple seasons and flower more than once. Perennial structures (rhizomes, stolons, crowns, entire plants or roots) survive from year to year.

Some weeds may be harmful to the environment or noxious to your regional ecology. For example Japanese Knotweed (Fallopia Japonica) is fast becoming a major weed problem on road side verges and urban landscape areas, a very difficult weed to eradicate. It is very important to recognise weeds and seek effective controls methods to eradicate them from our facilities.

Weeds can also be used as an indicator of soil conditions. For example, knotweed and plantains both indicate soil compaction because they can maintain adequate root respiration at lower oxygen diffusion levels than other plants. Different weeds tolerate different soil conditions, some are alkaline loving and others acid loving. Getting to understand and recognise the physiology of these plants will help you become better turfgrass managers.

This week's weed is: Horsetail Equisetum arvense

Scientific name


Life cycle

Equisetum arvense



Form / Appearance Horsetail is a hardy perennial. It grows to about 450mm high. It looks like a fern. Horsetail does not flower, but reproduces its self from producing spores, that are easily distributed by wind and water. The plant has very evasive roots that spread very quickly, having the ability to penetrate deeply into most soils. Once established it is a very difficult to remove and eradicate. horsetail-pic.jpg
Roots Roots can penetrate very deep into soils, Roots have been seen to grow down to two metres in depth. The plant also produces numerous rhizomic growths, which enable the plant to colonise areas quickly. Making it a very difficult plant to remove.
Flowers No flowers, the plant produces cones that reproduce spores for reproduction.
Leaves Leaves scale like, deciduous and inconspicuous. horsetail-leaves.jpg
Reproductive method Spreads from extensive rhizomes. Even short segments of broken rhizomes will sprout and grow. Spores from the cones will be dispersed by wind and water. Once in contact with the soil the spores can quickly germinate under moist conditions.

Spores can remain in the soil for many years, which again make this weed very difficult to eradicate.


Habitat Horsetail is a very common wild plant, which will grow in almost any type of soil but prefers damp, sandy, partially shaded areas. Seen in a wide variety of habitats. including gardens as a pernicious weed! and and be readily seen at waste tips, the edges of roads and railway tracks and pathways. horsetail-path.jpg
Miscellaneous info Horsetails (Equisetum species) are among the oldest plants on earth. Although they've become considerably smaller, with some now only a few cm's tall, they have not changed significantly in shape over the centuries. It does not flower but carries spores similarly to ferns. Romans always used horsetail to clean their pots and pans. Because it has been around so long it has been used for a wide range of medicinal purposes.

Other common names include: Common Horsetail, Foxtail, Horsetail, Bottlebrush, Horse Pipes, Pipe Weed, Cat's Tail, Mare's Tail, Pinetop, Pine Grass, Snake Grass, Shave Grass.

Cultural Control Once this weed gets established, it is often difficult to remove or eradicate. However, there are a number of ways now being used to eradicate or reduce the spread of this weed. In most cases they are labour intensive:
  • Pulling the weed is a common cultural practice of controlling horstail, removing the weed from site. Care should taken to ensure the whole root is removed to prevent the weed re-establishing. Often a time consuming process.
  • Digging out the plant. Often this process must be repeated a number of times to remove all signs of roots and rhizomes.
  • Removing all contaminated soil from site. not always a cost effective or viable method.
  • During the summer cut back plants that are beginning to die back to stop the spores spreading.
  • Mowing is an effective way of controlling the growth of these plants. Regular mowing will keep the growth down but will not kill the plant.

  • "Duty of Care" regulations, made under the Environmental Protection Act, 1991, which means you must dispose of any cut material at a registered disposal site.

Chemical Control Apply non-selective herbicides when plant growth is active. There are a number of products available for controlling Horsetails. These chemicals are best used when the weeds are actively growing, usually between April-October. Particular care should be taken when using chemicals near to water courses, rivers, streams and ponds.

Horsetails are susceptible to herbicides containing dichlobenil. Herbicides should be applied in the early spring when growth is active.

  • Casoron G. (contains 6.75% w/w dichlobenil) Rigby Taylor.

  • Finale (contains 120g/litre,11.33%w/w glufosinate-ammonium) Bayer Environmental Science.

  • Roundup pro biactive. (Contains 360g/L glyphosate). Scotts.
  • Roundup Pro Green. (contains 450g/l glyphosate present as 590g/l (50.9% w/w) of the isopropylamine salt of glyphosate. Rigby Taylor.
  • Timbrel (Contains 667g/L(44.3%w/w) triclopyr butoxy ethyl ester. (480 g/L triclopyr acid equivalent).

These herbicides are usually applied as a liquid using watering cans, knapsack sprayers and vehicle mounted sprayers.

Ensure you follow manufacturer's directions, health & safety and product data sheets, and comply with COSHH regulations, when using these chemicals.

Herbicides are an effective tool where high quality turf is desired. However, they must be applied with care and accuracy and in the context of a good overall turf management program. Before using any herbicide, carefully review the label for conditions of use including rates, methods of application, and precautions. Never use a herbicide in any manner contrary to its label and be sure that the herbicide will not injure the turfgrass species

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